Mk-11 vs. SR25 DMR style rifle

[alamo5000]

I'm looking for longer range, but I have no delusions of "precision" targeting at long distance (call it 800-900 yards). I'll be tickled to hear the gong. That doesn't mean I want to slap together a shit rifle, or spend a fortune, either. I. Probably leaning toward 7.62, upper mid-grade stuff with a really nice trigger, bolt and optic. My SBR and carbine will be completed following upgrades of the optics and rails. Everything else is top shelf, so that's how I want to do this up

When I have been going shooting for the last couple dozen times my go to spot is a standing 1,500 yard (ish) range.

So far with a .308 bolt action rifle with a 24" barrel we were tagging the plate at 1000 yards with 168 grain SMK rounds. Shooting that far in my experience with that gun was stretching the far end of the spectrum for that set up. 800 yards or so is not a problem one bit.

With my AR15 I've gotten out to hit the 800 yard plate. I am going to try for novelty's sake to go farther than that.

800 yards and in your choice of optic is 'less critical' but going past that out to 1000 yards or more and you really need to take special care on what you choose in that regard. At 1000 yards with the .308 we had to dial in a bunch of MOA pretty much to the point that we almost ran out of adjustment on the scope.

At 1000 yards the round had 36 feet of drop based on our dope.

Needless to say if you are shooting out to hear a gong at those distances that's fine. It's doable. It's not like I shoot at living things that much (I haven't hunted in a long time-- not opposed to it but I just haven't really gotten into it that much for a variety of reasons). I've shot deer before and bambi tastes great but I wouldn't think about shooting anything alive at those ranges unless I just had to.

With my AR I can easily crater a cantaloupe at 300 yards and despite being able to go almost 3 times past that I don't think I would shoot anything farther than that unless it was just an emergency. With that .308 I might go 600 yards ish given the right situation.

For me in my experience unless you know specifically how far a target is you will be there all afternoon trying to get a hit. Ranging out targets at long distances always will have some measure of error unless you have some other way to do it that isn't manual. If your range estimates are off you won't hear a gong. The farther you go out the more critical it becomes to know your exact ranges and to know your ammo.

[Joelski]

Great info, thanks guys and keep it coming!

I'll def. check out the MEGA set. Shooting for me is for personal gratifcation alone. I have thought about 3 gun, but haven't made it past that stage. I just don't have to compete to have a blast shooting. The longer range stuff is merely to see if I can do it, or potentially learn anything that my real life sniper buddies try to teach me, but my eyes glaze over when they start talking about math stuff. Pure knuckledragger blood. :) As I've said many times, I can shoot at a pop can at my feet and have as good a time as anybody just from hearing my weapon go BANG! :D I do practice speed drills and off-hand, sub-optimal shooting stuff, so I'm not a kook, I just prefer to keep it fun for myself so it doesn't turn into a job, like I did with racing mx, or playing guitar in bands in my youth.

So here's a question: The MK11-Mod 0 spec says the SWS is rated out to 1,500 yards... Is that because they have the time and ammo to fire in arcs all day and get proficient at hitting targets that far off, or what?

[Slippers]

Sorry I meant 175 gr. Brain fart. 168, 178, blah. Posting too late at night or early in the morning. :)

[Joelski]

Try the Smooth Operator from Lock-n-Load Java.

[Slippers]

I even have a few boxes of 175 gmm sitting beside me so I fail.

As much as I'd like coffee I'd rather try to sleep in between screaming hungry baby moments.

[Joelski]

So, I figure what got me all crossed up was some recent stuff I read about 18" being the sweet spot for long range gas rifles because of resonance of the longer barrels. The consensus seemed to be that 18" was the best compromise of length for accuracy while minimizing this. Sounds plausible to me, but I'm definitely not an expert, so I stop reading and start asking questions from experienced shooters. None of the guys I know that shoot long range for part of their paycheck place much in the AR platform for accuracy at long range, i.e. fine for what I want, but they prefer a bedded barrel and receiver for high accuracy guns. I have an older Weatherby 300M, but there's no fun in making something of my own, which like a lot of people, is the draw of AR's for me just like with guitars; I can assemble what I want from parts I like and tune it to my desire. Luthiery is very similar to gunsmithing, except you work with wood.

If there is a thread discussing the differences between Armalite and DPMS specs, could somebody please direct me? Why has the industry allowed this? Is the commercial base really that big that DPMS can deviate from Armalite/Stoner's design, or are the mods that compelling?

[alamo5000]

So, I figure what got me all crossed up was some recent stuff I read about 18" being the sweet spot for long range gas rifles because of resonance of the longer barrels. The consensus seemed to be that 18" was the best compromise of length for accuracy while minimizing this. Sounds plausible to me, but I'm definitely not an expert, so I stop reading and start asking questions from experienced shooters. None of the guys I know that shoot long range for part of their paycheck place much in the AR platform for accuracy at long range, i.e. fine for what I want, but they prefer a bedded barrel and receiver for high accuracy guns. I have an older Weatherby 300M, but there's no fun in making something of my own, which like a lot of people, is the draw of AR's for me just like with guitars; I can assemble what I want from parts I like and tune it to my desire. Luthiery is very similar to gunsmithing, except you work with wood.

If there is a thread discussing the differences between Armalite and DPMS specs, could somebody please direct me? Why has the industry allowed this? Is the commercial base really that big that DPMS can deviate from Armalite/Stoner's design, or are the mods that compelling?

My AR has a 16" barrel and so far I've taken it out to 800 yards (as I said). Next time I might try to hit 900 or a 1000 just to see if I can do it. With a longer barrel you do not gain accuracy. You can velocity. Read up on barrel length vs velocity loss. Every inch you take off you lose so many FPS.

With an equivalent 18" AR barrel on my rifle the only real difference would be the amount of MOA you end up dialing in. It won't be drastic differences between 16" vs 18" or whatever but there is a critical barrel length where it will just fall off the chart. You will have a few MOA difference between a 2650 fps round vs a 2800 fps round but it's nothing that isn't impossible to deal with. There are a number of articles online that give some measure of data about how much velocity loss you get. I shot the 1000 yards with a 24" barrel so realistically speaking it might not be that much more difficult to do with an 18" barrel because the velocity loss but that's something you need to figure out.

I would recommend looking up ammo. I use Hornaday's website. It has all the info there and it also has a ballistics calculator. With that you can plug in the numbers and see what kind of range you are at least in theory talking about. The more accurate the data the more accurate the results. I can tell you this much though, at 1000 yards trying to figure out 1/4 of an MOA is going to be difficult. The environment alone will cause some changes to your trajectory. A 90 degree wind or a quarter angle wind or whatever can and will have an effect.

Honestly though don't worry too much about the math. Knuckle dragger or not it's not some obscenely crazy math. Plus I have a calculator and an MOA calculator on my phone. Just plug in the numbers and it tells me what to do.

That said if you aren't measuring your factors (ie velocity) you probably won't be hitting at really far distances.

Again though if you go to 800 yards and in (with a .308) all this stuff has less of an effect.

[Joelski]

Taking notes. Much appreciated!

[gatordev]

I even have a few boxes of 175 gmm sitting beside me so I fail.

I figured it was an autocorrect issue, but either way, your point still stands. 168 is pretty squirrelly at 1K.

So here's a question: The MK11-Mod 0 spec says the SWS is rated out to 1,500 yards... Is that because they have the time and ammo to fire in arcs all day and get proficient at hitting targets that far off, or what?

I'm not sure where that number is coming from. .308 can certainly shoot past 800m, but 800-1000m is going to be the max effective range. If you've got enough real estate, you could shoot out to 2K, it just gets harder. Also keep in mind that the .308 round is pretty slow, so the farther you shoot, the more lead time you may need if your target is moving. Probably not a concern for you, but it's an interesting thing to keep in mind.

Regardless, I can tell you my SR-25 ECR will shoot out to 1K, consistently, and I am of the opinion that there are far more accurate AR-10-style rifles out there. Those Ultramatch barrels Rainier Arms has are pretty nice.

[Joelski]

That's what I'm thinking. Gotta get my Apex money back Somehow! :s

[jdhill]

18" 5.56 would be the mk12. There are several variants which use different stocks and handguard systems. If you want something that is very close to the "real" thing, Monty at Centurion Arms sells a mk12 mod 1 upper receiver group. All the reviews I've ever seen for it are excellent.

If you want to roll your own you can save a lot of weight by using a different handguard than the mod 0 PRI tube or mod 1 KAC RAS.

Off the shelf barrel choices I would consider:
WOA 18" SPR
Noveske 18" SPR
BCM 18" SS410

Or go crazy and get a Krieger, or Shilen, etc.

Find a nice scope, scope mount and your favorite trigger, and the rest of the parts are just filling in.

Here is a roll your own example of the above...

[UWone77]

Here is a roll your own example of the above...

I love the looks of the old PRI tube with the full top rail.

I would have gone with the SOPMOD, and a 2.5-10x32 optic, but that's just personal preference. Looks good!

[Joelski]

That's a fine lookin' roll your own! Looks like it has some reach to it.

[jdhill]

I love the looks of the old PRI tube with the full top rail.

I would have gone with the SOPMOD, and a 2.5-10x32 optic, but that's just personal preference. Looks good!

Actually is a 2.5-10x44 Vortex PST... the 32mm wasn't out when I put it together (and couldn't afford a NF at the time), and have been working on other projects since then... The SOPMOD would have been closer to "correct" but I want what works better for me (and the PRI rail instead of the ARMS already made it not an exact clone), although I am considering switching it out for a CTR with an LT RISR...

[Slippers]

I love the looks of the old PRI tube with the full top rail.

I would have gone with the SOPMOD, and a 2.5-10x32 optic, but that's just personal preference. Looks good!

I agree, love the old PRI tubes. Too bad they *still* cost over $300. Ugh. I wanted to switch to one when I rebuilt my 18" setup last month.